Calculations
FireShield Technical Reference Manual
A.3
Notification appliance voltage drop calculation
NAC 1 voltage drop calculations
Circuit length
Total circuit
current [2]
Wire resistance
per 1000 ft [1]
Voltage
drop
feet
x
amps
x
Ω
÷
1000 =
Panel
voltage
Voltage
drop
End of line
voltage [3]
Voltage
drop
Panel
voltage
Voltage
drop %
[4]
–
=
÷
[4]
=
NAC 2 voltage drop calculations
Circuit length
Total circuit
current [2]
Wire resistance
per 1000 ft [1]
Voltage
drop
feet
x
amps
x
Ω
÷
1000 =
Panel
voltage
Voltage
drop
End of line
voltage [3]
Voltage
drop
Panel
voltage
Voltage
drop %
[4]
–
=
÷
[4]
=
NAC 3 voltage drop calculations
Circuit length
Total circuit
current [2]
Wire resistance
per 1000 ft [1]
Voltage
drop
feet
x
amps
x
Ω
÷
1000 =
Panel
voltage
Voltage
drop
End of line
voltage [3]
Voltage
drop
Panel
voltage
Voltage
drop %
[4]
–
=
÷
[4]
=
NAC 4 voltage drop calculations
Circuit length
Total circuit
current [2]
Wire resistance
per 1000 ft [1]
Voltage
drop
feet
x
amps
x
Ω
÷
1000 =
Panel
voltage
Voltage
drop
End of line
voltage [3]
Voltage
drop
Panel
voltage
Voltage
drop %
[4]
–
=
÷
[4]
=
Notes
[1] Use 3.5
Ω
for 12 AWG and 2.5 sq mm wire, 5.2
Ω
for 14 AWG and 1.5 sq mm wire, 8.0
Ω
for 16 AWG and 1.0 sq mm wire,
and 13.0
Ω
for 18 AWG and 0.75 sq mm wire.
[2] Use the filtered 20 Vdc Average Operating Current ratings found on the installation or catalog sheet of each device.
[3] Cannot drop below 17 Vdc.
[4] 18.6 V for 230 V at 50 Hz, 18.8 V for 230 V 60 at Hz, 18.9 V for 120 V at 60 Hz
Summary of Contents for FireShield FS1004
Page 1: ...FireShield Technical Reference Manual P N 3100353 Rev 3 0 12MAY03 ...
Page 10: ...System overview and operation 1 8 FireShield Technical Reference Manual ...
Page 40: ...Programming 3 18 FireShield Technical Reference Manual ...
Page 42: ...Maintenance 4 2 FireShield Technical Reference Manual ...
Page 60: ...Panel specifications D 2 FireShield Technical Reference Manual ...
Page 66: ...Index Z 4 FireShield Technical Reference Manual ...
Page 68: ......